TISSUE PLASMINOGEN-ACTIVATOR AND PLASMINOGEN-ACTIVATOR INHIBITOR IN PATIENTS WITH LIVER-CIRRHOSIS

The behaviour of tissue plasminogen activator (t-PA) and t-PA inhibitor (PAI) was studied in patients with decompensated liver cirrhosis. t-PA antigen showed a 3-fold significant increase with respect to healthy volunteers. t-PA activity in these patients did not significantly differ from that found in the controls, but the specific activity of t-PA was significantly lowered by 63%. PAI activity was significantly reduced in cirrhosis (-67%), while PAI-1 antigen was increased by 24%. Venous occlusion of the arm for 20 min induced similar increases of t-PA antigen both in normal subjects and cirrhotic patients. These findings show that the total amount of t-PA is enhanced in liver cirrhosis, with no increase of t-PA activity due to the capacity of PAI to bind increased circulating t-PA antigen. The increased total amount of t-PA in cirrhotic patients could be explained in terms of a reduced clearance by the hepato-endothelial system.